Electric plug and receptacle



Aug. 29, 1944. H, .M. DEYSHER ELECTRIC PLUG A-ND RECEPTACLE Filed Dec. 16, 1942 2 Sheets-Sheet 1 I INVENTOR:

' HarI/eyMD BY F D 0 WITNESSES:

4 ATTORNEYS.

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Aug. 29, 1944. H. M. DEYSHER ELECTRIC PLUG ANDRECEPTAGLE Filed P60. 16, 1942 2 Sheets-Sheet 2 FIG Zr 2 25 VIII/[I7 I III JNVENTOR: flarveyllfleysiwr,

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Patented Aug. 29, 1944.

UNITED STA-TES- PATENT OFFICE 9 Claims.

This invention relates to electrical connectors I and has, more particularly, reference to the plugand-receptacle type useful for attaching lamps and domestic appliances to an electric supply circuit.

Connectors of the type referred to as heretofore generally constructed involve a plug with two prongs designed to effect separation between the positive and negative sides of the circuit conductor included in the outlet or receptacle.

Furthermore the top of each receptacle is usually provided with a suitable insulation between the two openings through which the plug prongs are entered to effect the desired electrical connection. Such structures possess, in general, one serious disadvantage; to wit, the difliculty encountered in getting the plug prongs initially entered, and more frequently, when the receptacle is located in a baseboard, for example, and troublesome to reach, the difiiculty of pluggingin is considerably increased.

The primary object of this invention is to overcome the above noted disadvantages by provision of a novel form of electric plug and associated receptacle wherein the plug is, in eiIect, self-centering, irrespective of the location of the receptacle, even though the latter be in an obscure comer and somewhat inaccessible.

Another object is to provide an improved electric plug and receptacle wherein the plug is definitely self-centering with respect to the receptacle slots, so that the operation of plugging-in is eifected with a minimum of-effort.

A further object of: this invention is the 'provision of what may be conventiently termed, a unit plug necessitating but one opening in the associated receptacle plate; the same being simple in construction, durable in character, and which positively prevents shocking .incidental to efiecting the electric connection.

While the stated objects areindioative in'a general way of the aims of this invention others, with ancillary advantages, will become apparent to those skilled in the art upon an understanding of said invention hereinafter disclosed; while it will be evident that changesin the details may be effected without departing from the spirit and scope of the concluding claims.

In the drawings Fig. I is a face view of an electric outlet embodying the present improvements.

Fig. II is a section through the same, or, as taken on the plane II-II of Fig. III.

Fig. III is a section on the plane III-Ill of Fig. 1!.

Fig. IV is a section on the plane IV--IV of Fig. V, with theimproved. plug of this invention in active position in respect to the receptacle.

Fig. V is a similar section'on the plane V-"V of Fig. IV.

Fig. VI is a ragmentary side view of the insert portion or prongof the improved plug.

\Fig. VII is an edge view of the same;

Fig. VIII is "a section taken as indicated by the angle-arrows VIII-VIII .in Fig. VI, and drawn to larger scale.

Fig. IX is a sectional view, similar to Fig. IV, of a modified form of the invention and taken on the plane IX-IX of Fig. X.

Fig. X is a section taken substantially as indicated by the angle-arrows X-X in Fig. IX.

Fig. XI is a fragmentary sectional view to better illustrate an alternate form of plug-entering bevel included in the receptacle of Figs. IX and X. l 1

Fig. XIII is a top plan view of the plug-in body component with the electric cord removed.

Fig. XIII is a perspective viewillustra'tive of how the improved ,plug of this invention. shown by Figs. IV and V more particularly, may be initially placed with respect to one of the, receptacle openings;and,

plug similarly characterized 2.

Fig. XIV is a similar illustration, to the precedin but showing how easily the entering portion of the plug may be said to self-center itself, as hereinafter more fully explained.

In describing the forms of this invention exemplified-by the above captioned drawings, specific terms will be employed for the sake of clarity, but it is to be understood the scope of said invention is not thereby limited, each such term being intended to embrace all reasonable equivalents which perform the same function for an analogous purpose.

Referring more in detail to he drawings, the outlet of this invention is com rehensively designated by the reference character I, and the novel The outlet I. it is to be observed, includes a rectangular metal Junction box 3, for reception of the plug-receptacle 4, preferably made of suitable insulation material, and having attached thereto-the wallplate 5 of corresponding material. The wallplate 5 is shown in Fig. 1, by way of example only, as of the multi-slot or gang type; that is to say, it is provided with four elliptical inwardlytapering holes 8 in registration above a complemental series of spring contacts, I, I, projecting from conductor strips 8. 8, seated in grooves 8 in the body portion it of the plug-receptacle 4. v

Each contact 1 has an associated contact prong H to which the respective conductor wires l2, l3 ior supplying electric current to the plug receptacle 4 are secured by appropriate-means l4. The wall-plate 3 is attached to the Junction-box 3 by screws l3, passed through apertures |3 therein, engaging in threaded holes l1 in end.

flanges i8 laterally projecting from said box; while the plug-receptacle 4 is secured to-the wall-plate 5 by screws l9, Fig. 111 in an obvious manner; and, it is to be particularly noted the said plug-receptacle embodies a medial division or separator partition 23 intermediate the spring contacts 1, said partition having longitudinally spaced taper-section reductions in register below the wall-plate holes 3, and the purpose or which is hereinafter iully explained.

Referring now to the novel plug 2, see Figs. IV'

and V, the same consists of a hollow body portion 2|, of suitable insulating material, having an axial aperture 22 at one end for free entrance of a conventional electrical cable 23, the

individual conductors 24, 25 of which are coupled by means 23 to the terminals 21, 23 of said plug. The terminals 21, 23 are in the form of strips suitably secured to the fiat paralleling sides 23 of an insulate material spacer-unit 30, conveniently of the section best understood from Figs.

IV and V; that is to say said spacer unit embodies an approximately elliptical-section shank 3| with the opposed. minor arcs planed down, or

otherwise reduced, as best understood from Fig. VIII, to define the parallel sides 29, above referred to; an intermediate discous portion 32 with appropriate holes 33 for snug passage of the terminals 21, 28; and a flat key-portion 34 for attachment thereto of the upper ends of the respective terminals 21,28 by the coupler means 23.v Particular attention is directed, at this point, to the fact that the free end portion of the shank 3| is medially slotted at 35 to a crosssection complemental with respect to, and for coaction with, the selected partition separator portion 20 of the plug receptacle 4, as readily understandable ,on reference to Figs. IV and IX of the drawings; whereas the sides of the free end portion of the shank 3| are transversely corrugated and pointed, at 33, 31 respectively, see Figs. VI and VII to best advantage, with the contronting portions of the terminal strips 21, 23 matingly-shaped for inset relation in respect'to -.the forward point or tip 33 oi said shank 3|.

The shaping of the free end portion of the shank 3|, as just described, greatly assists the spacer unit 33 in automatically turning about its longitudinal axis and finding the proper position to slide into the selected elliptical hole 3 in the receptacle wall-plate 3. as hereinafter explained.

In order to accommodate turning movement oithe terminal spacer unit 33, relative to the plug body portion 2|, the discous part 32 thereo! is conveniently seated in a stepped-boring 33 in said body portion, with retention against axiallyunit or plug-in part 30' embodies a main section 44 for fitment into the plug elliptical-part 4|,

with securement therein as by a-set-screw 43, and the shank extension 3|; while the terminals 21', 28 project through theholes 33' spacedly outward and beyond the main section 34.

Having detailed the structural aspects of the invention, the ease and facility with which the plug 2 or 2 is engaged to the receptacle 4 or 4' is, as follows: When the plug spacer unit 33 or 33' is placed on any part of the wall-plate 5 and I moved about until the point or tip 38 or 33', F18.

IX, thereof hits the bevel of any one of the elliptical holes 8 or 3' of said wall-plate-see Fig.

XIII, regardless of what the position of shank portion 3| or 3| may be, it the top of the-body portion 2| of the plug 2 or the grasp 430i the plug 2', be held between the fingers, as shown, and a very slight pressure exerted thereon, the tip 33 or 33 of said plug will be caused to automatically revolve and assume the position illustrated in Fig. XIV, or enter the hole 6 or 3' respectively. Inward pressure on the plug-2 or 2' next causes the terminals 21, 28 or 21', 28 to automatically coact between the spring contacts 1 or 1', with the shank slot 35, or '33 Fig. IX,

straddling the partition taper-section associated reduction 20', in an obvious manner. It is to be here noted the spring-contacts .1 and 1' are approximately shaped for mating with the parts 3B, 31, or 36, 31' of Fig. IX, 0f the terminals 21,

28, or 21', 28, so as to ensure efiicient electric conductivity and snap-retention of the plug 2 or 2', in operative :position. Should the elliptically-shaped end portion of the plug shank 3| or 3| happen to coincide immediately with the correspondingly shaped wall-plate hole 3 or 3', the above-described manipulation of the plug 2 or 2' becomes unnecessary. In this connection the plate holes 6 or 6' may be formed with opposed relatively-inclined slight recessions as in-- dicated at 3" in Fig. XI, aligned with'the major axis of the plug shank 3| or 3| of Fig. 1x to facilitate passage oi the parts 33, 31- and 33 or 33', 31' and 33' into entering position between the spring contacts 1 or 1'; while it will be selievident the plug 2 or 2 can be easily seated by anyone, even though the outlet or is located directed shifting by means of a spring-ring 43,

in a dark corner.

From the foregoing it is thought the merits an advantages or this invention will be readily understood; while it is to be noted the insulation that formerly was exterior in respect to the wallplate 3 or 3' is, in accordance with said invention, now located below said plate, see the part or partition 23 or 23, which provides positive insulation between the spring contacts 1 or 1', when' the plug 2 or 2' is in position and thereby prevents the placing of any article between or across said contacts. This feature is highly important as it effectively eliminates the possibility of transmission qiany shocks." Furthermore it will be observed from Figs. Inn and XIV that the position of the hand, while inserting the plug 2 or 2', remains practically stationary after the tip 33 or 33' oithe shank 3| or 3| has once contacted the bevel surface oi any one or the wallplate holes 3 or 3, incident to the tact that in both forms of the plug shown, said tip andadreduced cylindrical extension II joining parts 35, 31 or a, 31' enable theunit If it or it" to revolve about its longitudinal axis while the body portion 2!, or the ferrule-like cap 68, is held stationary. Again. the plugreceptacle. l or d may be made in two parts and into one unit as shown; orit-may'be formed as two units similar to conventional receptacles and have a separate wall plate: however both t are designed for fitment into standard.

elliptical contour for coaction with the free end of the plug extension, to impart rotary self-centering motion to said unit in respect to the receptacle aperture. I a

'2. An electric plug and receptacle comprisin an insulat material hollow body; a similar material plug-in unit in said body with an ellipti al-section axial extension, said extension having s flats aligned with its major axis for pport of current-conductive terminals, an undulate-ta free end including a medial slot;-

and an ting material receptacle having an aperture of inclined elliptical contour with a subiaoent partition oi conformatory section to that oi plug-4n unit-slotted free end whereby. when said unit's free end is moved into with eliiptically contoured aperture, rotary self-centering motion is imparted to the plug-in unit and its free end slot is engageable across the partition aid;

3. An electric plug and receptacle in accordance with claim 2 wherein the hollow body and plugin unit are relatively rotatable, the elliptical-section extension medial slot is of wedge-formation. and said eon embodies longitudinal flats with lateral corrugations adjoining its outer end for application thereto of correspondina portions oi the current-conductive d. An electric plug and receptacle in accordance with claim 2 wherein the plug-receptacle embodies an inverted wedge shape partition for motion with the medial slot in the plus-i unit free. end, and spring contacts parallel such partltion, d contacts embodying undulats-portions for ting coaction with complemental parts of the current-conductive terminals. j

den electric plug and receptacle in accordance with claim 2 wherein the hollow'body includes a main elliptical part with a relativelyreduced cylindrical extension, the plug-in unit embodies a section for attachment in the hollow body main elliptical part, and said hollow body is provided with a free ferrule like grasp which permits the hollow body and attached unit to rotate in respect to said grasp.

8. The combination with an electric receptacle of the type described, of a plug-in unit comprising a tubular body of insulating materialincluding sections of diflerential diameter, a terminal carrying member of similarmaterial rotatively mounted in the larger section of the tubular. body, said member having an elliptical-section axial extension with an undulate-tapering free end and an open medial slot, and means whereby said plug-in unit is rotatively held in the tubular body Y 7. An electric plug and receptacle as defined in claim 2 wherein the terminal carrying portion of theplug-in unit comprises an approximately elliptical-section shank with the opposing minor arcs longitudinally-reduced to define parallel hats, for application thereto of terminal strips; a discous portion having appropriate holes for snug passage therethrough or said strips; a flat key portion for joint attachment of the terminal strips and the lead-oil wires; lateral corrugations with mergent taperings are formed across the free end of the shank aforesaid to define an insulating tip for the unit; and an open-end inwardly convergent slot is formed across the" free end of said shank for the purpose specified.

8. An electric plug and receptacle as defined in claim 2, wherein the terminal carrying member embodies an integrally formed discous portion; the tubular body is provided with a stepped portion in its bore; and a spring ring coacts with said discous portion to retain the terminal carrylog member in the tubular body against axial shifting. i

9, In an electrical plug andreceptacle, of the type described, a plug-in unit comprising a tubular body, of insulating material, a main elliptical-section and a relatively reduced cylindrical portion. a ferrule-like'grasp at the outer end of said cylindrical portion aiiording rotation of the unit relative thereto; 'a coniormatory section terminal carrying member of similar material for engagement in the tubular body main section; means whereby said tubular body and; terminal carrying member are held against relative movement: and an axial elliptical-section shank es tending outwards'irom the carrying member,

said shank having an undulate-tapering free and including a medial wedge-shaped slot, for the purpose specified.

HARVEY M. DEYSHER; 

